An ongoing effort to reduce drag in vehicular structures and associated cargo enclosures is of great importance as fuel economy becomes an increasingly large consideration in the overall design of a vehicle and/or its associated cargo enclosure. As the drag increases, the amount of fuel needed to move the vehicle also increases due to the greater energy required to overcome the drag. For instance, it has been stated that for a vehicle traveling at 70 mph, about 65% of the total fuel consumption of the vehicle's engine is used to overcome drag. Therefore, even a small reduction in the drag experienced by a vehicle traveling at highway speeds can result in a significant improvement in fuel economy.
For instance, heavy-duty vehicles such as tractor-trailers (also known as semi tractors, tractors, class 8 long haul trucks, transfer trucks, 18-wheelers, semis, etc.) have a tall and wide box-shaped profile that creates a significant amount of drag compared to smaller vehicles on the road. For instance, Table I lists common drag coefficients of road vehicles.
TABLE IType of VehicleDrag Coefficient (Cd)Low Drag Production Car.26Typical Sedan .3-.35Sport Utility Vehicle.4-.5Pick-up Truck.4-.5Conventional Class 8 long haul.59-.63tractor trailers
Additionally, conventional cargo enclosures often have a similarly tall and wide box-shaped profile that creates a significant amount of drag. For example, trailers typically define an enclosed cargo space that is rectangular in shape. For example, the most common type of cargo trailer in the U.S. is a dry box van that is 53 feet long.
Various devices have been developed in the past to address certain areas of drag on a vehicle and/or its associated cargo enclosure, such on a tractor-trailer combination. However, these devices often have significant limitations in their ability to reduce drag and/or their ability to be easily integrated into fleet operations. As a result, a comprehensive solution for reducing vehicle drag is still needed.
Thus, a need exists for an improved aerodynamic fairing(s) that is designed to provide drag reduction for a cargo enclosure that is included within or configured to be coupled to or hauled by a vehicle. Retrofit kits for incorporating such devices onto a cargo enclosure would also be beneficial. Moreover, methods relating to the utilization of such devices would also be beneficial.